Investigation of Acoustic Properties in Casing for Water-Filled Wells Pipe

To enable long-distance communication within water injection well tubes, we leverage hydroacoustic communication technology for the required research. This study presents a theoretical analysis and experimental measurements of transmission attenuation in a steel pipe with a 110 mm diameter and 110 m length, fully filled with water. Based on the findings, it is recommended that acoustic signals be transmitted at frequencies no lower than 4346 Hz. Hydroacoustic signals were measured across frequency ranges of 2 kHz to 13 kHz and 4 kHz to 13 kHz, revealing average attenuation rates of 14 dB and 19 dB per 100 m, respectively. These values are lower than the geometric propagation attenuation observed in free space. As the frequency increases, attenuation also increases, in alignment with both theoretical predictions and empirical observations. The experimental results further demonstrate that the attenuation pattern in the frequency domain follows a logarithmic trend within the well pipe.